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1.
Opt Express ; 32(9): 15667-15679, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859212

RESUMO

We report on the theoretical and experimental investigations of optical microcavities consisting in the plane-plane arrangement of a broadband high-reflectivity mirror and a suspended one-dimensional grating mirror possessing a high-quality factor Fano resonance. By varying the length of these cavities from the millimeter to the few-micron range, we observe at short lengths the reduction of the spectral linewidth predicted to occur for such a Fano cavity as compared to a conventional broadband mirror cavity with the same length and internal losses. Such narrow linewidth and small modevolume microcavities with high-mechanical quality ultrathin mirrors will be attractive for a wide range of applications within optomechanics and sensing.

2.
Cerebrovasc Dis ; 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38185109

RESUMO

INTRODUCTION: Structured models for secondary prevention of stroke in community settings are scarce. We aimed to develop and evaluate a model for improving medication adherence and enhanced risk factor monitoring. METHODS: We developed a multimodal C-CHW-I model for stroke survivors. Following training, all patients received a minimum of three CHW home visits, and once in 3-month telephone-call and health education for six months by CHWs. Seven blocks from 16 blocks of the study area were randomised to additionally receive an SMS alert for six months to reinforce CHW involvement. The primary outcomes were medication adherence and risk factor monitoring, and the secondary outcome was risk factor control. RESULTS: The mean age of the study population was 64+12 years, 765(85%) had ischaemic stroke. In the overall study cohort receiving the CHW intervention, mean medication adherence significantly improved from 3.56(0.88) at baseline to 3.78(0.61) at 6 months; p<0.001. Overall risk factor monitoring improved from 42.7% to 49.7%, and mean (standard deviation) systolic blood pressure (SBP) significantly reduced from 138(21) mmHg to 132(15) mmHg at 6-months; p<0.001. In patients additionally receiving SMS-based intervention, a statistically significant improvement in medication adherence was seen at 3 months (3.76+0.64 versus 3.61+0.81; p=0.008) however no difference persisted at 6 months. The proportion of smokers and alcohol users reduced in both groups with a trend to greater reduction in the intervention group (smokers:5.9% versus 2.8% (p=0.446) and alcohol users: 1.6% versus 1.4%(p=0.474)). At six months, the SBP did not differ (SBP (132.1(16.2) in the SMS group versus 133.2(15.8) mmHg in the control group, p=0.409). CONCLUSION: Our model improved medication adherence and risk factor monitoring of stroke survivors in community settings, and this can reduce stroke burden in the community.

3.
Int J Biometeorol ; 68(7): 1235-1252, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38691211

RESUMO

There are concerns regarding high surface temperatures on synthetic grass sports surfaces influencing the surrounding thermal environment, potentially increasing heat stress and impacting athlete safety. As such, studies have investigated changes to the thermal environment surrounding synthetic grass surfaces in comparison to both natural grass, and synthetic surfaces with different features, but this body of research has not been systematically reviewed. Therefore, this systematic review aimed to (i) determine if there are differences in the thermal environment surrounding synthetic grass surfaces compared with natural grass surfaces, and (ii) determine if there are differences in the thermal environment between different types of synthetic grass surfaces. A systematic review adhering to the PRISMA guidelines was performed. The eligibility criteria required investigations to report at least one of the following environmental parameters on or directly above both a synthetic surface and a comparator group of either natural grass or an alternative synthetic grass surface used in sport: Air temperature, mean radiant temperature, humidity, wind velocity, unified heat stress indices (i.e. wet-bulb-globe temperature and heat index) and/or surface temperature. Twenty-three studies were identified. The only parameters that were consistently higher on synthetic grass compared to natural grass were the air temperature (range: 0.5-1.2 °C) and surface temperature (range: 9.4-33.7 °C), while the mean radiant temperature, humidity, wind velocity and wet-bulb-globe temperature remained similar or required more data to determine if any differences exist. Synthetic grass surfaces consisting of styrene butadiene rubber infill or a shock pad had increased surface temperatures, whereas surfaces with thermoplastic elastomer infill, Cool climate turf fibres or HydroChill had lower surface temperatures. This systematic review has demonstrated that air and surface temperatures can be increased on synthetic sports surfaces, compared to natural grass surfaces. However, it is uncertain whether the differences are enough to increase an individual's heat stress risk and cause concern for athlete safety. While modifications to the turf infill or fibres can reduce synthetic surface temperatures, the effect of these features on the thermal environment as a whole is unclear. This review was prospectively registered with the Open Science Framework (Open Science Framework registration   https://doi.org/10.17605/OSF.IO/BTKGE ).


Assuntos
Poaceae , Esportes , Humanos , Temperatura , Propriedades de Superfície
4.
Bioinformatics ; 38(7): 2062-2063, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35104317

RESUMO

SUMMARY: Comparisons of protein structures are critical for developing novel protein designs, annotating protein functions and predicting protein structure. The template modeling score (TM-score) is a widely used but computationally expensive measure of protein similarity that is applicable to a wide variety of structural biology problems. We introduce TMQuery-a continuously updated database containing over eight billion pre-computed TM-score values for every pair of proteins in the Protein Data Bank, allowing researchers to quickly query and download TM-scores via a web interface. AVAILABILITY AND IMPLEMENTATION: Publicly available at https://tmquery.gsk.com/.


Assuntos
Proteínas , Software , Conformação Proteica , Proteínas/química , Bases de Dados de Proteínas
5.
Nanotechnology ; 34(38)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37336199

RESUMO

The superior properties, such as large interlayer spacing and the ability to host large alkali-metal ions, of two-dimensional (2D) materials based on transition metal di-chalcogenides (TMDs) enable next-generation battery development beyond lithium-ion rechargeable batteries. In addition, compelling but rarely inspected TMD alloys provide additional opportunities to tailor bandgap and enhance thermodynamic stability. This study explores the sodium-ion (Na-ion) and potassium-ion (K-ion) storage behavior of cation-substituted molybdenum tungsten diselenide (MoWSe2), a TMD alloy. This research also investigates upper potential suspension to overcome obstacles commonly associated with TMD materials, such as capacity fading at high current rates, prolonged cycling conditions, and voltage polarization during conversion reaction. The voltage cut-off was restricted to 1.5 V, 2.0 V, and 2.5 V to realize the material's Na+and K+ion storage behavior. Three-dimensional (3D) surface plots of differential capacity analysis up to prolonged cycles revealed the convenience of voltage suspension as a viable method for structural preservation. Moreover, the cells with higher potential cut-off values conveyed improved cycling stability, higher and stable coulombic efficiency for Na+and K+ion half-cells, and increased capacity retention for Na+ion half-cells, respectively, with half-cells cycled at higher voltage ranges.


Assuntos
Potássio , Sódio , Cátions , Ligas , Fontes de Energia Elétrica
6.
Jpn J Clin Oncol ; 53(4): 313-320, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36546704

RESUMO

BACKGROUND: Oral mucositis is the dose-limiting toxicity of chemoradiation in oropharyngeal cancer patients, which can be minimized by giving constraints to oral mucosa. However, the constraints defined in literature are extrapolated from chemoradiation in head and neck cancers as a whole. This study aims to determine oral mucosa dose-volume parameters that can predict grade ≥ 3 acute oral mucositis in oropharyngeal cancer patients treated with volumetric modulated arc radiotherapy. METHODS: This prospective study was done in 52 patients of locally advanced oropharyngeal cancer treated with Volumetric modulated arc radiotherapy. Dose-volume histogram data were extracted and then acute oral mucosa toxicity was analysed. Receiver operating characteristic analysis and logistic regression were carried out to determine predictive factors for grade ≥ 3 mucositis. RESULTS: Grade ≥ 3 acute oral mucositis occurred in 57.6% (30/52) patients in the study. V30Gy > 53.35% (P = 0.005) was an independent dosimetric factor related to grade ≥ 3 acute toxicity. In the receiver operating characteristic curve, the area under V30Gy was 0.770 (P = 0.001); the cut-off value of V30 was 46.23% (sensitivity, 0.80; specificity, 0.91). CONCLUSIONS: Dose-volume histogram analysis predicts V30 > 53.35% as independent factors for grade ≥ 3 acute oral mucositis in patients with oropharyngeal cancers treated with Volumetric modulated arc radiotherapy. Studies in future with more patient number can further validate the above results.


Assuntos
Mucosite , Neoplasias Orofaríngeas , Radioterapia de Intensidade Modulada , Estomatite , Humanos , Mucosa Bucal , Estudos Prospectivos , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Neoplasias Orofaríngeas/radioterapia , Estomatite/etiologia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos
7.
Bioorg Chem ; 141: 106860, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37748328

RESUMO

Nucleic acid represents the ideal drug candidate for protein targets that are hard to target or against which drug development is not easy. Peptide nucleic acids (PNAs) are synthesized by attaching modified peptide backbones generally derived from repetitive N-2-aminoethyl glycine units in place of the regular phosphodiester backbone and represent synthetic impersonator of nucleic acids that offers an exciting research field due to their fascinating spectrum of biotechnological, diagnostic and potential therapeutic applications. The semi-rigid peptide nucleic acid backbone serves as a nearly-perfect template for attaching complimentary base pairs on DNA or RNA in a sequence-dependent manner as described by Watson-Crick models. PNAs and their analogues are endowed with exceptionally high affinity and specificity for receptor sites, essentially due to their polyamide backbone's uncharged and flexible nature. The present review compiled various strategies to modify the polypeptide backbone for improving the target selectivity and stability of the PNAs in the body. The investigated biological activities carried out on PNAs have also been summarized in the present review.


Assuntos
Ácidos Nucleicos Peptídicos , Ácidos Nucleicos Peptídicos/farmacologia , RNA , DNA , Peptídeos/farmacologia , Sítios de Ligação
8.
Environ Res ; 217: 114733, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36402185

RESUMO

Biochar has been evaluated globally to improve soil fertility and mitigate climate change. However, the long-term effects of successive biochar application on carbon (C) accumulation in soil irrigated with saline versus non-saline water (canal water) has not been investigated. A field experiment was conducted to study the effects of rice straw biochar addition rates (0, 2, 4, 8 Mg ha-1) on C storage in soil irrigated with water of different electrical conductivity [EC, dS m-1]; 0.3 (non-saline canal irrigation water; CIW), 5 (saline irrigation water; SIW5), 10 (SIW10), and 15 (SIW15) in a cotton-wheat system. Long-term irrigation with saline water of variable EC levels adversely affected soil functions, reducing above-ground biomass in cotton (12-48%) and wheat (5-27%). In contrast, plots irrigated with saline water but amended with rice straw biochar showed significant improvement in aboveground biomass (both in cotton and wheat), possibly due to its beneficial effects on soil properties such as soil EC, organic carbon, microbial population, water and nutrient availability, bulk density, soil aggregation, and proliferation of roots. Interestingly, the change in total organic C (TOC) stocks (8.5, 17, and 27.5 Mg C ha-1) after 5 years were found to be almost double the amount of biochar C added (4.3, 8.6, 17.2 Mg ha-1), indicating stabilization of belowground C inputs from the root biomass by the applied biochar and also possibly through its physical interaction with aggregates and minerals. Even though biochar application to saline water irrigated plots increased the contribution of plant-derived C to overall soil TOC stocks, it was still lower compared with canal water irrigated plots. The study conclusively established that the long-term stabilization of biogenic C through biochar has essential implications for mitigating climate change by accumulating additional C beyond the recalcitrant C contained in biochar.


Assuntos
Carbono , Oryza , Solo , Carvão Vegetal
9.
Mar Drugs ; 21(3)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36976225

RESUMO

Astaxanthin (3,3-dihydroxy-ß, ß-carotene-4,4-dione) is a ketocarotenoid synthesized by Haematococcus pluvialis/lacustris, Chromochloris zofingiensis, Chlorococcum, Bracteacoccus aggregatus, Coelastrella rubescence, Phaffia rhodozyma, some bacteria (Paracoccus carotinifaciens), yeasts, and lobsters, among others However, it is majorly synthesized by Haematococcus lacustris alone (about 4%). The richness of natural astaxanthin over synthetic astaxanthin has drawn the attention of industrialists to cultivate and extract it via two stage cultivation process. However, the cultivation in photobioreactors is expensive, and converting it in soluble form so that it can be easily assimilated by our digestive system requires downstream processing techniques which are not cost-effective. This has made the cost of astaxanthin expensive, prompting pharmaceutical and nutraceutical companies to switch over to synthetic astaxanthin. This review discusses the chemical character of astaxanthin, more inexpensive cultivating techniques, and its bioavailability. Additionally, the antioxidant character of this microalgal product against many diseases is discussed, which can make this natural compound an excellent drug to minimize inflammation and its consequences.


Assuntos
Antioxidantes , Clorofíceas , Antioxidantes/farmacologia , Disponibilidade Biológica , Xantofilas/farmacologia , Xantofilas/química , Carotenoides
10.
J Arthroplasty ; 38(8): 1602-1612.e1, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36805118

RESUMO

BACKGROUND: While aspirin is acceptable for venous thromboembolism (VTE) prophylaxis following total joint arthroplasty in most patients, more potent agents are used in patients considered higher risk for VTE. We evaluated the efficacy and safety of aspirin versus potent anticoagulation agents following total knee arthroplasty (TKA) and total hip arthroplasty (THA). METHODS: A cohort study of 72,288 TKA and 35,142 THA from the Kaiser Permanente Total Joint Replacement Registry was performed (2009 to 2019). Identified medications were aspirin, factor Xa inhibitors, low-molecular-weight heparin (LMWH), and warfarin. A validated VTE risk score was assigned to each patient. Propensity score-weighted logistic regressions were used to evaluate 90-day VTEs. Noninferiority testing was performed with a margin of 1.25 using the upper bound (UB) of the 1-sided 95% CI. RESULTS: For TKA, aspirin was not inferior to LMWH (odds ratio [OR] = 0.77, UB = 1.09) and warfarin (OR = 0.64, UB = 0.90); there was no evidence to support noninferiority of aspirin compared to factor Xa inhibitors. Findings were consistent for THA (LMWH: OR = 0.59, UB = 0.75; warfarin: OR = 0.69, UB = 0.89). TKA was considered higher risk for VTE, whereas aspirin use demonstrated noninferiority compared to warfarin (OR = 0.54, UB = 0.81), we lacked evidence of noninferiority when compared to LMWH and factor Xa inhibitors. We lacked evidence of noninferiority of aspirin versus any potent anticoagulation in higher-risk THA. CONCLUSION: Aspirin was found to be effective and safe for VTE prevention in primary total joint arthroplasty, including in patients considered higher risk for VTE. LEVEL OF EVIDENCE: III.


Assuntos
Artroplastia de Quadril , Tromboembolia Venosa , Humanos , Aspirina/efeitos adversos , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle , Heparina de Baixo Peso Molecular/efeitos adversos , Varfarina/efeitos adversos , Artroplastia de Quadril/efeitos adversos , Estudos de Coortes , Inibidores do Fator Xa/uso terapêutico , Anticoagulantes/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle
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